Same Model, Different Harness, Worlds Apart: I Read DeepSeek Harness's Source. Here's What's Actually New.
· 14 min read
The model is the soul. The harness is the body.
The model thinks. The harness does.
Hi, I'm Booker.
Today I'm taking apart DeepSeek Harness (dsh), open-sourced by DeepSeek yesterday (2026-08-13).
This is not a secondhand recap. I read the source and the official docs. I'll walk through its three real design decisions, pour some cold water, and honestly tell you my first run failed.